Bound by Flame is an action RPG set in a fantasy universe. The player controls the mercenary Vulcan who protects the lands against a siege by the seven ice lords and their minions. He starts as an experienced fighter in the game, but early on he messes up summoning a fire demon and instead becomes possessed by it. This introduces a duality that forms the backbone of the game, as he can either attempt to restore his humanity or give in to the possession and embrace the powers. This change is guided through his actions, either helping villagers or working against them, and not only leads to visual change - either restoring the human form or slowly transforming into a fiery demon - but also to branching story paths with multiple endings.
The game offers three skills trees (fighter, ranger and pyromancer) each with their own abilities. The fighter path stresses melee combat with swords, axes and warhammers. Vulcan is able to chain together attacks into combos and also needs to dodge and parry incoming attacks. Ranger introduces a stealthy path, for instance offering twin daggers to sneak up from behind or spells that for instance slow down time for enemies. Pyromancer delves into the fire powers of the possession offering all kinds of spells, explosives, traps and weapons enhanced with fire. The skills are divided into four tiers: novice, amateur, expert and master - narrowing the choices with each new tier. All of the paths lead to an ultimate ability. While fighting it is possible to switch stances between warrior and rogue. The game offers a selection of companions and includes weapon crafting with various modifiers.
Rather than an open-world RPG, it divides the game world into smaller hubs, one for each chapter, offering freedom to explore and do quests in any order until the entire hub is complete, and then moving on to the next chapter. A mini-map is the bottom right corner helps navigating areas.